JPH09210592A - Leak inspection equipment for tube type heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide leak inspection equipment for a tube type heat exchanger which dispenses with temporary support members or the like. SOLUTION: Leak inspection equipment for a tube type heat exchanger so devised that covers 19 and 20 which cover connected parts of a heat transfer tube 7 inserted into and connected to through holes 6 of tube plates 4 and 5 and can be brought into airtight contact with the outer surfaces of the tube plates 4 and 5 are fitted with pressure to the opposite-end opening parts of the heat transfer tube 7 to be inspected in regard to leak so as to seal the heat transfer tube 7 hermetically, that compressed air (c) is injected into the heat transfer tube 7 through an air piping 13 connected to the covers 19 and 20 and that a defect brought about in the heat transfer tube 7 is detected by recognizing visually a change of the pressure of the injected compressed air (c) shown in a pressure gage 15. A tensile member 24 stretching along the axis of the heat transfer tube 7 and projecting outside through the covers 19 and 20 is provided and nuts 25 which make it possible to fit the covers 19 and 20 closely on the outer surfaces of the tube plates 4 and 5 by adding a tensile force to the tensile member 24 are provided at the end parts of the tensile member 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a leak inspection device for a tubular heat exchanger.

[0002]

2. Description of the Related Art FIG. 4 is a sectional view showing an outline of an example of a tubular heat exchanger for exchanging heat between two kinds of fluids via heat transfer tubes. A heat exchanger casing 1 has a primary fluid inlet 2 at its upper end and a primary fluid outlet 3 at its lower end.

The front end surface of the heat exchanger casing 1 (see FIG. 4)
The high temperature side tube sheet 4 is provided on the (A side) and the low temperature side tube sheet 5 is provided on the rear end surface (B side in FIG. 4).

A large number of through-holes 6 (see FIG. 5) are provided at positions on the respective surfaces of the high temperature side tube sheet 4 and the low temperature side tube sheet 5 which face each other.
(See FIG. 5), both ends thereof are inserted into the through holes 6 facing each other, and the terminals at both ends are expanded radially outward as shown in FIG. A heat pipe 7 is provided, and by connecting the high temperature side tube sheet 4 and the low temperature side tube sheet 5 by the heat transfer tube 7, opposing through holes 6 are formed so as to communicate with each other via the heat transfer tube 7. .

In FIG. 4, 8 is a heat exchanger casing 1
Is a secondary fluid inlet duct connected to the front end of the heat exchanger casing 1, and 9 is a secondary fluid outlet duct connected to the rear end of the heat exchanger casing 1.

The primary fluid (arrow a) flows into the heat exchanger casing 1 from a primary fluid inlet 2 provided at the upper end of the heat exchanger casing 1 and flows between a large number of heat transfer tubes 7.
The primary fluid outlet 3 provided at the lower end of the heat exchanger casing 1 flows out of the heat exchanger casing 1.

On the other hand, the secondary fluid (arrow b) is a secondary fluid inlet duct 8 connected to the front end of the heat exchanger casing 1.
Flow through the heat transfer tubes 7 connected to the through holes 6 of the high temperature side tube sheet 4, and flow out to the space on the low temperature side tube sheet 5 side connected to the heat transfer tubes 7 through the through holes 6. Then, it flows out of the heat exchanger casing 1 from the secondary fluid outlet duct 9 connected to the rear end of the heat exchanger casing 1.

Thus, heat exchange is performed between the primary fluid (arrow a) and the secondary fluid (arrow b) via the heat transfer tube 7.

Of the large number of heat transfer tubes 7, some of the heat transfer tubes 7 have minute holes due to corrosion or the like, or the connecting portions between the tube plates 4 and 5 and the ends of the heat transfer tubes 7. When a minute gap is generated in the area, the fluid with a higher pressure leaks from those portions and the two types of fluid are mixed with each other, and the heat exchange efficiency is reduced. Is regularly performed.

FIG. 6 shows an example of a conventional leak inspection apparatus. The heat transfer tubes 7 are provided on the outer surfaces of the high temperature side tube sheet 4 and the low temperature side tube sheet 5 to which both ends of the heat transfer tube 7 to be inspected are connected. A pair of lids 11 and 12 formed so as to cover the connecting portion
Are abutted via an annular seat packing 10 formed of rubber or the like, an air pipe 13 is connected to the lid 11 on one side, a cock 14 is provided in the middle of the air pipe 13, and the lid 11 is inserted from the cock 14. The pressure gauge 15 is arranged in the middle of the side air pipe 13, and the secondary fluid inlet duct 8 is used to press the lids 11 and 12 against the outer surfaces of the high temperature side tube sheet 4 and the low temperature side tube sheet 5, respectively. Further, the temporary support members 16 and 17 are provided inside the secondary fluid outlet duct 9, and the jacks 18 are arranged between the temporary support members 16 and 17 and the lids 11 and 12.

Then, the jack 18 is actuated to press the respective lids 11 and 12 against the outer surfaces of the high temperature side tube sheet 4 and the low temperature side tube sheet 5, and then the cock is checked while checking the pressure gauge 15 of the air pipe 13. 14 is operated to open it, and from the pressure source (not shown) to the inside of the heat transfer tube 7 to be inspected.
The compressed air c is supplied via 1 and the change of the air pressure after closing the cock 14 is confirmed by the pressure gauge 15.

Thus, when the pressure indicated by the pressure gauge 15 is lowered, it can be detected that the heat transfer tube 7 is damaged in some way.

[0013]

However, in the leak inspection device for the tubular heat exchanger as described above, the temporary support members 16 and 17 and the jack 1 are required each time a leak inspection is performed.
There is a problem that the inspection time increases because the work for preparing No. 8 is required.

In view of the above situation, the present invention forms a temporary support member and the like by forming lids provided at both ends of the heat transfer tube so that they can be pressed against the tube sheet by a tension member inserted into the heat transfer tube. It is an object of the present invention to provide a leak inspection device for a tubular heat exchanger that does not require the.

[0015]

SUMMARY OF THE INVENTION According to the present invention, a lid which covers a connecting portion of a heat transfer tube inserted and connected to a through hole of a tube sheet and which can come into airtight contact with an outer surface of the tube sheet is to be subjected to a leak test. The heat transfer tube is hermetically sealed by crimping to both end openings of the heat tube, compressed air is injected into the heat transfer tube through the air pipe connected to the lid, and a change in pressure gauge pressure of the injected compressed air is visually confirmed. A leak inspecting apparatus for a tubular heat exchanger, which detects a defect caused in a heat transfer tube, wherein the tension extends along the axial center of the heat transfer tube and penetrates through the lid to project to the outside of the lid. A leak in a tubular heat exchanger, characterized in that a tensioning means is provided at the end of the tensioning member, which is provided with a member, and by which tension is applied to the tensioning member to bring the lid into close contact with the outer surface of the tube sheet. It is related to the inspection device.

The tension member may be formed by a wire and a screw rod connected to both ends of the wire, and a nut screwed to the screw rod may be used as the tension applying means.

Further, the tension member is formed by a plurality of links which are bent and pin-coupled to each other and a screw rod connected to both ends of the link, and a nut screwed to the screw rod is used as a tension applying means. You can also

According to the above means, the following effects can be obtained.

After the tension member is inserted through the heat transfer tube and the lid, tension is applied to the tension member by the tension applying means,
The tension causes the lid to be pressed against the outer surface of the tube sheet, thereby sealing the inside of the heat transfer tube.

Further, when the tension member is formed by the wire and the screw rod and the tension applying means is formed by the nut screwed to the screw rod, when the nut is tightened, the tension is applied to the wire, and the tension is increased. The lid is pressure-bonded to the outer surface of the tube sheet, and the inside of the heat transfer tube is sealed.

Further, when the tension member is formed by the link and the screw rod and the tension applying means is formed by the nut screwed to the screw rod, when the nut is tightened, the tension is applied to the link, Due to the tension, the lid is pressed against the outer surface of the tube sheet to seal the inside of the heat transfer tube.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing an example of an embodiment for implementing a leak inspection device for a tubular heat exchanger according to the present invention. In the figure, the same components as those in FIGS. 4 to 6 are designated by the same reference numerals.

The outer surfaces of the high temperature side tube sheet 4 and the low temperature side tube sheet 5 including the connecting portion of the heat transfer tube 7 to be inspected, which is hollow and has one end open and the other end closed, are covered. Through-holes 21 are formed in the centers of the other end side end faces of the pair of lids 19 and 20 formed in, respectively, and the air pipe 13 is connected to one of the lids 19 and 20. A cock 14 is provided in the middle of the air pipe 13, and a pressure gauge 15 is arranged in the middle of the air pipe 13 on the lid 19 side of the cock 14.

A wire 22 which can be inserted into the heat transfer tube 7
A threaded rod 23 that can be inserted into the through holes 21 of the lids 19 and 20 is fixed to both side ends of the tension member 24.

When the wire 22 of the tension member 24 is inserted into the heat transfer tube 7 to be inspected, the threaded portion of the threaded rod 23 is projected to the outside of the respective lids 19 and 20 by an appropriate length. Shall have such a length.

By providing a length adjusting mechanism (for example, a turnbuckle) at an intermediate portion of the tension member 24,
The length of the tension member 24 may be adjustable.

Further, a nut 25 that can be screwed into the threaded rod 23 of the tension member 24 and that applies tension to the wire 22 of the tensioned member 24, and that can be externally fitted to the threaded rod 23, and the lid 19 can be used. , 20 and the nut 25 are provided with packing 26 respectively interposed.

Next, the operation of the illustrated example will be described.

When conducting a leak inspection of the heat transfer tube 7, the sheet packing 10 is provided on the outer surface of each of the high temperature side tube sheet 4 and the low temperature side tube sheet 5 to which both ends of the heat transfer tube 7 to be inspected are connected. The lids 19 and 20 are brought into contact with each other, and the wire 22 of the tension member 24 is inserted into the through hole 21 of each of the lids 19 and 20 and the heat transfer tube 7, and then the tension member 24.
The packing 26 is fitted onto the threaded rod 23 of the
Is tightened and the nut 25 is tightened to apply tension to the tension member 24 and pressurize the packing 26.

When tension is applied to the tension member 24, the respective lids 19 and 20 come into close contact with the outer surfaces of the high temperature side tube sheet 4 and the low temperature side tube sheet 5 via the sheet packing 10 by the tension and pressurize. The compressed sheet packing 10 is compressed to maintain airtightness between the lids 19 and 20 and the tube sheets 4 and 5, and at the same time, the pressurized packing 26 is applied to the lids 19 and 20 and the screw rod 23.
And acts to maintain airtightness between the nut and the nut 25.

After that, while checking the pressure gauge 15 of the air pipe 13, the cock 14 is operated to open it, and the compressed air is introduced from the pressure source (not shown) into the heat transfer tube 7 to be inspected through the lid 19. The pressure gauge 15 confirms the change in the air pressure after supplying c and closing the cock 14.

Thus, when the pressure indicated by the pressure gauge 15 decreases, it can be detected that the heat transfer tube 7 is damaged in some way.

Therefore, according to the illustrated example, the lids 19 and 20 mounted on both ends of the heat transfer tube 7 to be inspected by the tension member 24 formed by the wire 22 and the screw rod 23 are attached to the high temperature side tube sheet 4 and the low temperature side. It becomes possible to crimp each side tube plate 5 to the outer surface thereof, and the temporary support members 16 and 17 as in the conventional example shown in FIG. 6 are not required, and each time the leak inspection is performed, the temporary support members 16 and 17 are provided. Since it is possible to omit the work of preparing the jack 18 and the jack 18, the inspection time can be significantly shortened.

Further, since the pulling member 24 uses the wire 22 having a certain degree of flexibility, it is difficult to carry in the long rod-shaped body because the space on the outer surface side of the tube sheets 4 and 5 is narrow. Even in such a case, after carrying the wire 22 in a state in which it is wound in multiple layers to either one of the outer surface sides of the tube sheets 4 and 5, the wire 22 is sequentially fed out and inserted into the heat transfer tube 7. You can

FIG. 2 is a cross-sectional view of another embodiment of the embodiment of the leak inspection device for a tubular heat exchanger according to the present invention. In the figure, the same parts as those in FIG. 1 are designated by the same reference numerals.

In the example of FIG. 2, a plurality of links 27 which can be inserted into the heat transfer tube 7 to be inspected are foldably connected by a pin 28 like a folding scale, and screw rods 29 are pinned to both ends of the link 27. The pulling member 24 is configured by connecting with the pulling member 30.

Other than the above, there is no difference from the leak inspection device for the tubular heat exchanger shown in FIG.

Next, the operation of the example of FIG. 2 will be described.

When conducting a leak inspection of the heat transfer tube 7, the sheet packing 10 is provided on the outer surface of each of the high temperature side tube sheet 4 and the low temperature side tube sheet 5 to which both ends of the heat transfer tube 7 to be inspected are connected. The lids 19 and 20 are brought into contact with each other, and the links 27 of the tension members 24 are inserted into the through holes 21 of the lids 19 and 20 and the heat transfer tube 7, and then the tension members 24 are inserted.
The packing 26 is fitted on the threaded rod 29 of the
Is tightened and the nut 25 is tightened to apply tension to the tension member 24 and pressurize the packing 26.

When tension is applied to the tension member 24, the respective lids 19 and 20 are brought into close contact with the outer surfaces of the high temperature side tube sheet 4 and the low temperature side tube sheet 5 via the sheet packing 10 by the tension, and pressed. The compressed sheet packing 10 is compressed to maintain airtightness between the lids 19 and 20 and the tube sheets 4 and 5, and at the same time, the pressurized packing 26 is applied to the lids 19 and 20 and the screw rod 29.
And acts to maintain airtightness between the nut and the nut 25.

Thereafter, while checking the pressure gauge 15 of the air pipe 13, the cock 14 is operated to open it, and the compressed air is introduced from the pressure source (not shown) into the heat transfer tube 7 to be inspected through the lid 19. The pressure gauge 15 confirms the change in the air pressure after supplying c and closing the cock 14.

Thus, when the pressure indicated by the pressure gauge 15 decreases, it can be detected that the heat transfer tube 7 is damaged in some way.

Therefore, according to the example of FIG.
The lids 19 and 20 mounted on both ends of the heat transfer tube 7 to be inspected can be crimped to the respective outer surfaces of the high temperature side tube sheet 4 and the low temperature side tube sheet 5 by the tension member 24 formed by the screw rod 29 and the screw rod 29. As with the leak inspection device for the tubular heat exchanger shown in FIG. 1, the temporary support members 16 and 17 as in the conventional example shown in FIG. 6 are not required, and the temporary support is performed each time the leak inspection is performed. Since the work of preparing the members 16 and 17 and the jack 18 can be omitted, the inspection time can be greatly shortened.

Further, in the case of the example shown in FIG. 2, since the tension member 24 is formed like a folding scale, the space on the outer surface side of the tube sheets 4 and 5 is narrow, and it is difficult to carry in the long rod-shaped body. Even in such a case, after the tension member 24 is folded and carried into one of the outer surfaces of the tube sheets 4 and 5,
The link 27 of the tension member 24 can be inserted into the heat transfer tube 7 while being developed in sequence.

The leak inspection apparatus for a tubular heat exchanger according to the present invention is not limited to the above-mentioned illustrated example,
For example, a threaded rod 23 forming the tension member 24 shown in FIG.
As shown in FIG. 3, it is formed by an eyebolt, and the wire 2 is attached to a threaded rod 23 formed by the eyebolt through a thimble 32.
2 may be connected, and in the above-mentioned illustrated example, 1
The case where the lids 19 and 20 that can cover the vicinity of the ends of the heat transfer tubes 7 are provided has been described, but if the lids that can cover the ends of the plurality of heat transfer tubes 7 in a wide range are provided, a plurality of covers can be provided at a time. Needless to say, various changes can be made without departing from the scope of the present invention, such as performing a leak inspection of the heat transfer tube 7.

[0047]

As described above, according to the leak inspection device for a tubular heat exchanger of the present invention, various excellent effects as described below can be obtained.

(1) With the tension member, the lids attached to both ends of the heat transfer tube to be inspected can be brought into pressure contact with the respective outer surfaces of the tube sheet, and a temporary support member or a jack is provided each time a leak inspection is performed. It is possible to omit the work of preparing.

(2) Therefore, the inspection time can be greatly shortened.

[Brief description of drawings]

FIG. 1 is a cross-sectional view schematically showing an example of an embodiment of a leak inspection device for a tubular heat exchanger according to the present invention.

FIG. 2 is a cross-sectional view showing the outline of another example of the embodiment of the leak inspection device for the tubular heat exchanger of the present invention.

FIG. 3 is a side view schematically showing a modification of the tension member related to FIG.

FIG. 4 is a sectional view schematically showing an example of a heat exchanger.

5 is a cross-sectional view of the pipe expansion joint portion of the heat transfer tube end portion related to FIG. 4;

FIG. 6 is a cross-sectional view schematically showing an example of a conventional leak inspection device for a tubular heat exchanger.

[Explanation of symbols]

 4 High Temperature Side Tube Sheet (Tube Sheet) 5 Low Temperature Side Tube Sheet (Tube Sheet) 6 Through Hole 7 Heat Transfer Tube 13 Air Piping 15 Pressure Gauge 19 Lid 20 Lid 22 Wire 23 Screw Rod 24 Tensile Member 25 Nut (Tension Applying Means) 27 Link 28 pin 29 screw rod

Claims (3)

[Claims] 1. A lid which covers a connecting portion of a heat transfer tube inserted and connected to a through hole of the tube sheet and which can come into airtight contact with an outer surface of the tube sheet is crimped to both end openings of the heat transfer tube to be leak-inspected. The heat transfer tube was sealed by means of the above method, compressed air was injected into the heat transfer tube through the air pipe connected to the lid, and the change in the pressure gauge pressure of the injected compressed air was visually confirmed to cause the heat transfer tube. A leak inspection device for a tubular heat exchanger for detecting a defect, comprising: a tension member extending along an axis of a heat transfer tube and penetrating the lid to project to the outside of the lid. A leak inspecting apparatus for a tubular heat exchanger, comprising tension applying means for applying a tension to bring the lid into close contact with an outer surface of a tube sheet at an end portion of the tension member. 2. The tubular heat exchanger according to claim 1, wherein the tension member is formed by a wire and a threaded rod connected to both ends of the wire, and a nut screwed to the threaded rod serves as tension applying means. Leak inspection device. 3. A tension member is formed by a plurality of links in which pins are bendably bent and a threaded rod connected to both ends of the link, and a nut screwed to the threaded rod is used as a tension applying means. 1. The leak inspection device for a tubular heat exchanger according to 1.